Apolipocrustacein, formerly vitellogenin, is the major egg yolk precursor protein in decapod crustaceans and is homologous to insect apolipophorin II/I and vertebrate apolipoprotein B

BACKGROUND: In animals, the biogenesis of some lipoprotein classes requires members of the ancient large lipid transfer protein (LLTP) superfamily, including the cytosolic large subunit of microsomal triglyceride transfer protein (MTP), vertebrate apolipoprotein B (apoB), vitellogenin (Vtg), and insect apolipophorin II/I precursor (apoLp-II/I). In most oviparous species, Vtg, a large glycolipoprotein, is the main egg yolk precursor protein. RESULTS: This report clarifies the phylogenetic relationships of LLTP superfamily members and classifies them into three families and their related subfamilies. This means that the generic term Vtg is no longer a functional term, but is rather based on phylogenetic/structural criteria. In addition, we determined that the main egg yolk precursor protein of decapod crustaceans show an overall greater sequence similarity with apoLp-II/I than other LLTP, including Vtgs. This close association is supported by the phylogenetic analysis, i.e. neighbor-joining, maximum likelihood and Bayesian inference methods, of conserved sequence motifs and the presence of three common conserved domains: an N-terminal large lipid transfer module marker for LLTP, a DUF1081 domain of unknown function in their central region exclusively shared with apoLp-II/I and apoB, and a von Willebrand-factor type D domain at their C-terminal end. Additionally, they share a conserved functional subtilisin-like endoprotease cleavage site with apoLp-II/I, in a similar location. CONCLUSION: The structural and phylogenetic data presented indicate that the major egg yolk precursor protein of decapod crustaceans is surprisingly closely related to insect apoLp-II/I and vertebrate apoB and should be known as apolipocrustacein (apoCr) rather than Vtg. These LLTP may arise from an ancient duplication event leading to paralogs of Vtg sequences. The presence of LLTP homologs in one genome may facilitate redundancy, e.g. involvement in lipid metabolism and as egg yolk precursor protein, and neofunctionalization and subfunctionalization, e.g. involvement in clotting cascade and immune response, of extracellular LLTP members. These protein-coding nuclear genes may be used to resolve phylogenetic relationships among the major arthropod groups, especially the Pancrustacea-major splits

Egg production in the euryhaline tilapia, Sarotherodon melanotheron heudelotii, experimentally maintained in fresh, sea and hypersaline waters

Through the experiments presented here we wanted to test whether egg production of the black-chinned tilapia Sarotherodon melanotheron heudelotii under experimental conditions varies as a function of ambient salinity (fresh waters vs. sea waters vs. hypersaline waters, 0, 35 and 70, respectively) and whether these responses differ between fish acclimated within a few weeks from fresh water to saline and hypersaline environments (experiments E1 and E2, monitoring over 10 and 18 weeks), and individuals born and raised all life long at the experimental salinities (E3, monitoring over 18 weeks). In total, 233 spawns were collected. In each of the three experiments, the reproductive investment (gram of egg per gram of female over 2 weeks) did not differ between salinities of 0 and 35, whereas it was 2-3 times lower at 70 than at 0-35, because of lower spawning frequency (E1-E3), smaller clutch size (E1) and lower spawn mass (E1-E3). Finally, fish acclimated to salinity from fresh water over a few weeks and those maintained at a particular salinity all life long showed similar reproductive traits, thereby emphasizing the remarkable physiological plasticity of this species

Genetic diversity of Boeseman's Rainbowfish (Melanotaenia boesemani) reared in Indonesian farms compared to endangered natural populations

Endemic to two lakes (Ayamaru and Uter) of West Papua (Indonesia), the Boeseman's Rainbowfish Melanotaenia boesemani Allen & Cross, 1980 is a very popular ornamental freshwater fish. As a result, this rainbowfish species faces great threats and is on the red list of endangered species. Therefore, rearing of this species in aquaculture systems appears to be a promising solution to limit capture of wild specimens and prevent its extinction. Although its reproduction cycle has been controlled for more than 30 years, very few farms still raise M. boesmani, probably due to the problems reported by the farmers, such as decline of production, higher proportion of females per spawning, loss of coloration, lower growth rate and fecundity. Using 12 microsatellites previously developed for this species, comparison of genotypes within six farms around Jakarta indicated that all reared strains originated from Ayamaru Lake. No deficit in heterozygotes was evidenced, suggesting that there was no major inbreeding in these reared populations. Genotype analysis also suggested that M. boesemani species is a metapopulation composed of genetically differentiated populations. Altogether, these results indicate that the problems experienced by the farmers are due not to inbreeding depression but to other factors such as inadequate management and/or poor water quality. Yet, increasing aquaculture production is probably the most effective way to alleviate the pressure that M. boesemani faces in its natural environment

Plasticity of gene expression according to salinity in the testis of broodstock and F1 black-chinned tilapia, Sarotherodon melanotheron heudelotii

The black-chinned tilapia Sarotherodon melanotheron heudelotii Ruppell 1852 (Teleostei, Cichlidae) displays remarkable acclimation capacities. When exposed to drastic changes of salinity, which can be the case in its natural habitat, it develops quick physiological responses and keeps reproducing. The present study focused on the physiological impact of salinity on male reproductive capacities, using gene expression as a proxy of acclimation process. Two series of experimental fish were investigated: the first one was composed of fish maintained in freshwater for several generations and newly acclimated to salinities of 35 and 70, whereas the second one consisted of the descendants of the latter born and were raised under their native salinity. Expression patterns of 43 candidate genes previously identified from the testes of wild males was investigated in the three salinities and two generations. Twenty of them showed significant expression differences between salinities, and their predicted function revealed that most of them are involved in the osmotic tolerance of sperm cells and/or in the maintenance of sperm motility. A high level of expression variation was evidenced, especially for fish maintained in freshwater. In spite of this, gene expression patterns allowed the differentiation between fish raised in freshwater and those maintained in hypersaline water in both generations. Altogether, the results presented here suggest that this high variability of expression is likely to ensure the reproductive success of this species under varying salinities

Portrait of Hatchery Management Profile on Rainbow Fish Melanotaenia boesemani (Allen & Cross, 1980) Cultivation in Jakarta Area

Hatchery managers and maintaining genetic diversity and fitness population in endangered and threatened species in pond is a important and difficult thing to do.  But is must to do for conservation biology.  Fitness and structure population depends on effective breeding number (Ne) and population connectivity between each other. The second most important thing is gene flow and genetic drift. Ne is major role in the maintenance of genetic diversity as indicator for inbreeding depresion and genetic drift.  We sampled 6 hatchery in Jakarta  and Bekasi Indonesia region and used 12 polymorphic microsatellite loci to quantify population genetic structure. Result in this study are, each farm have different methode. The old farmers is bapak Gusi and bapak Hasan (+30 years).  Ne in bapak Hasan and bapak Gusi hatchery is 66,667 and F value is 0,00749 and loosing allele (P) is 0,26183.  Compared with younger farmers bapak Yahya (5 years) have Ne = 133,333, F = 0,00375 and P = 0,06855.  Even though hatchery bapak Hasan and bapak Gusi have the same value Ne, F and P but the result in population structure they are different founder populations. Hatchery bapak Hasan have unique structure and alleles composition compared with other hatchery.Keywords: breeding, management, Melanotaenia boesemani, hatchery, population

STATUS KESEHATAN IKAN LELE (Clarias gariepinus) YANG MENERIMA PAKAN BERSUPLEMEN KOMBINASI DAUN SIRIH (Piper betler leaf), JAMBU BIJI (Psidium guajava leaf), DAN KIPAHIT (Tithonia diversifolia leaf)

Tanaman obat telah banyak digunakan sebagai bahan pencegah dan pengobatan penyakit pada ikan budidaya. Penelitian ini ditujukan untuk mengetahui status kesehatan ikan lele (C. gariepinus) yang menerima pakan dengan suplemen tanaman obat kombinasi dari daun sirih, jambu biji, dan kipahit melalui pengamatan gambaran darah dan histologi ginjal sebagai organ yang memproduksi darah. Kombinasi satu merupakan kombinasi dari ketiga daun tanaman obat masing-masing sebanyak 33%, kombinasi dua juga terdiri dari daun sirih, jambu biji, dan kipahit masing-masing sebanyak 5%:19%:76%, dan kontrol yaitu pakan tanpa penambahan tanaman obat. Gambaran darah dan histologi ginjal diamati pada minggu ketiga setelah pemberian pakan. Hasil pengamatan gambaran darah menunjukkan bahwa terdapat peningkatan jumlah sel darah merah pada ikan yang menerima pakan perlakuan dibandingkan dengan kontrol (0,4 ± 0,14). Namun tidak terdapat perbedaan nyata antara jumlah sel darah merah dari kelompok perlakuan kombinasi satu dan dua (1,5 ± 0,17 dan 1,4 ± 0,1). Jumlah sel darah putih pada kelompok perlakuan juga meningkat dibandingkan dengan kelompok kontrol (10,5 ± 0,46), namun tidak terdapat perbedaan nyata antara kelompok perlakuan kombinasi satu dan dua (15,1 ± 1,19 dan 17,6 ± 1,14). Hasil pengamatan histologi terlihat jaringan hematopoietik organ ginjal dari kelompok yang menerima perlakuan berproliferasi lebih banyak dibandingkan kelompok kontrol. Namun tidak ada pengaruh pada nilai hemoglobin dan persentase leukosit diferensiasi antara kelompok perlakuan dan kontrol. Penambahan daun tanaman obat dalam pakan ikan mampu meningkakan status kesehatan dari ikan lele.Medicinal herbs have been traditionally used as prophylactic and therapeutic supplement to treat diseases in aquaculture. This study was aimed to improve the health quality of catfish (C. gariepinus) through feeding on diets enriched with a combination of betel, guava, and tithonia as medicine by analyzing hematology and histology of kidney as blood producing organ. Diet-one was feed enrich with 33% of each plant. Diet-two was feed enriched with betel, guava, and tithonia at a proportion of 5%,19%, and 76%, respectively. Control diet was fed without the plants’ supplementation. Hematology and histology of fish kidney were observed after fish received three-week feed treatments. The results showed that there was an increase of erythrocyte levels in the treated fish groups fed with diet-one and diet-two compared with the control (0.4 ± 0.14). However, no significant differences of erythrocyte level were observed between fish groups fed with diet -one and die-two (1.5 ± 0.17 and 1.4 ± 0.1). Leucocyte levels also increased in the treated fish group with diet-one and diet-two compared to the control (10.5 ± 0.46). However, there was no significant difference of leucocyte level between the fish group feed with diet-one and diet-two (15.1 ± 1.19 and 17.6 ± 1.14). Histological observations found that there were more hematopoietic tissues in the fish kidney of proliferated treated group than the control group. However, there was no effect on hemoglobin level and leukocyte percentage differentiation between the treatment and control groups. This study concludes that medicinal herbs as enrichment ingredients in fish diet can increase the health quality of fish

Molecular tracing of viral diseases in aquaculture

Molecular Tracing of Viral Diseases in Aquaculture = Traçage Moléculaire des Maladies Virales en Aquaculture : Colloque, Montpellier (FRA), 2015/01/27-29International audienc